Homework on Consensus - Questions

Blockchain and Bitcoin 101
#2894
  1. A group of nodes, computers all need to be in agreement to reach conesnsus
  2. Consensus is irrefutable and doesnt depend on telling the truth. Conesus is reached on facts recorded in the blockchain. A central database depends on telling the truth and this can be manipulated
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#2895
  1. we need consensus in blockchain because its agroup of people deciding if the data is the truth
    2.central database can have info removed un like blockchain and data bases are desided by one persons
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#2896

  1. The process of verification by all parties in a network is called consensus. A public ledger in the internet is a database run by a network of computers where everyone can see all transactions. Blockchain is a public ledger running in the internet that cannot be forged. Truth equals the acceptance of a transaction to be added into the public ledger after being verified by all parties in the network. Ergo, truth is determined by consensus when a transaction is added into the blockchain since it has been verified and accepted by all the ntwk and cannot be forged.

  2. A central database is run by one single entity who can decide all the rules by which the database can be altered. If an external party wants to use the database, this external party will have to trust the database originator in telling the truth, since it will not have the power to verify the transactions and provenance of the entries in the database.

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#2897

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    It means that multiple independent participants in a blockchain network have verified that the entry to blockchain is following rules correctly. Participants in blockchain are incentivized to do this correctly by system of rewards and/or penalties. That process results in consensus.

  2. How is this different from how truth is determined in a central database?
    Truth in a central database is determined by everyone who has the power to change the database.
    It is faster and more efficient but requires you to trust the administrators.

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#2898

1-miners need to verify the claim of a person that “he owns bitcoin”, and then add his transaction to the blockchain .if the majority of miners agree about this claim , then they add it to the blockchain.

2- when the database is centralised , if the authority is corrupted, it might modify the database to be in line with its own benefits.

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#2899

What does it mean when we say that in blockchain, consensus determine the truth?

The network of nodes collectively decides the truth and in turn are Incentivised by payment.

How is this different from how truth is determined in a central database?

In a central data base a board of individuals decide the truth and we have to trust this is correct.

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#2900

Since Consensus in Built in incentive all the computer node have to come to agreement that Something is right or not. if the majority of the node agree on a transaction to be added to the network then it means it is legit.and verified .Hence determines the trust or validity of transaction but at the other end if it gets rejected then the that means it was not valid as claimed. hence the node that broadcast the transaction gets punished and vise versa

Centralized database the consensus is determined by signal Authority individual who could compromise the trust for various reasons.

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#2901

  1. It means that all of the information from the parties that are participating in storing their information (be it financial info, product information etc.) on the blockchain is visible by other parties and thus can be confirmed or rejected by other participants. If the majority of participants agree that an information provided by a participant (let’s say by a milk producer like in the video) is true, that information will be confirmed and stored on the blockchain as verified. Of course, this works only if the majority of the players that are participating in monitoring and confirming the information are not intentionally malicious.

  2. In the central database a central authority can determine by themselves what information gets stored in the database and how. There is no consensus and everybody working with them needs to TRUST that their data is correct and honest. Trust is in a particular player on the blockchain is not necessary because you can fact-check everything stored there - which means that blockchain is trustless.

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#2902
  1. It means that multiple parties have checked the information and they have verified that it is correct.
  2. A central database has a owner/operator that decides what truth is.
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#2903
  1. What does it mean when we say that in blockchain, consensus determine the truth?
    Any transaction in a blockchain can only be added if all the players in the network agree to do so, and for this to happen the players must be incentivised to allow only the correct transactions. So the players are incentivised to act truthfully.
  2. How is this different from how truth is determined in a central database?
    In a central database there is a need to trust that the governing authority will act truthfully. However this is not always the case
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#2904

  1. Consensus in the blockchain determines the truth by using financial incentives (mining) to have multiple computers honestly agreeing if a transaction has occurred or not.

  2. This is different from how truth is determined in a central database because a central database has a single authority of truth which can be corrupted. Because blockchain requires multiple computers to agree on the adding of a transaction to the ledger and those computers are financially incentivized to be truthful you prevent corruption or cheating from occurring.

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#2905

What does it mean when we say that in blockchain, consensus determines the truth?

It means that the same data is confirmed by different independent parties in the network, thus, eliminating the need for trust.

How is this different from how truth is determined in a central database?

In a central database, truth is determined by the trust in the party that provides the data. In the best case (not really), truth is determined by a third party’s corroboration that conducts an audit.

So truth in a central database, basically comes down to a marketing operation to create “trust” in people’s mind.

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#2906

What does it mean when we say that in blockchain, consensus determine the truth?
It means that the majority of blockchain nodes agree upon whether or not a pending transaction should be confirmed and put into the blockchain. If a transaction is added, then that now is the truth.

How is this different from how truth is determined in a central database?
In a central database, there is only one ledger, and therefore, whatever that ledger says is truth. There is no transparent way to know if the data has been modified in an incorrect or manipulated way.

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#2907

[quote=“ivan, post:1, topic:8425, full:true”]
Homework on Consensus - Questions

  1. What does it mean when we say that in blockchain, consensus determine the truth?
    Consensus = Transparency, removing the need for trust, as it is impossible to lie. Every action can be verified. Consensus works as every node is incentivized financially.
  2. How is this different from how truth is determined in a central database?
    There is no incentive, data can be manipulated as only one person entering the data.
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#2908

  1. It means all parties involved must agree it is true before it gets added to the blockchain and is then unchangeable

  2. in a central database a small party has control over what is put on it, and whatever they put on it, whether it is true or false, can not be changed by other parties other than themselves.

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#2909

What does it mean when we say that in blockchain, consensus determine the truth? The network is all separate (decentralized) and yet they must all agree therefore it has the highest probability of truth.

How is this different from how truth is determined in a central database? Truth can be manipulated.|

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#2910
  1. What does it mean when we say that in blockchain, consensus determine the truth?

The nature of the blockchain requires all information/transactions to be verified as correct by all before it can be added to the blockchain. This decentralised consensus determines truth. Once consensus has been achieved it is written to the blockchain and cannot be changed.

  1. How is this different from how truth is determined in a central database?

Truth in a centralised database is reliant on trusting that parties responsible for controlling and deciding what is truth. This centralised system can be changed and is open to manipulation.

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#2911

1 - consensus is like a validation of something in blockchain wich had been agreed by the ledger wich has incentives to tell truth.

2 - in a central database we need trust.

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#2912
  1. Lots of people/computer verify transx and give the vote in order to reach an agreement.
  2. Central database making decisions by themselves w/out asking anybody out of the group.
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#2913
  1. All parties agree or a majority of parties agree that a transaction (or other data) is correct & true before adding it to the ledger.
  2. Only one computer (and so one operator) change the state of entries, as opposed to a group.
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